Exercising good self-control is not enough to prevent girls from becoming obese, a new study has found.
Researchers from Ohio State University say that even girls who are the least impulsive at age two are more likely to become obese by age five.
However, male toddlers with the most will power are less likely to be obese than their peers by the time they reach school.
The researchers say their study, the first to show a difference between the genders when it comes to self-regulation and childhood obesity, raises questions about how our differing expectations for boys and girls may affect their obesity risk.
This could pave the way to understanding why girls put so much pressure on themselves from a young age – and how that internalized pressure could even result in metabolism changes that spike weight gain.
Exercising good self-control is not enough to prevent girls from becoming obese, a new study has found
The study analyzed data from the Early Childhood Longitudinal Study Birth Cohort of 6,400 US children born in 2001 to see if the ability to practice self-control at age two years old affected the risk of obesity in kindergarten.
The researchers note that a lack of self-control is associated with poor health, economic and social outcomes in adults.
Scientists visited the child’s home and assessed their behavior using four dimensions: adaptability, attention, persistence, and frustration tolerance.
Each dimension received a score from one to five so a child could receive anywhere from a total score of four, which meant a low level of self-regulation, to 20 – an indicator of high self-regulation.
Additionally, they used BMI (body mass index), a measure of body fat based on height and weight, to determine obesity.
Children with a BMI greater than or equal to the highest five percent were characterized as obese.
‘Observers were looking at things like how readily a child gave up a block when an adult said it was time to play with something else,’ said lead author Dr Sarah Anderson, an associate professor of epidemiology at Ohio State University.
“How difficult it was to hold their attention and how easily frustrated they became when things weren’t going their way.
‘Going in, we thought what many people think – that we would see lower rates of obesity as self-regulation increased.’
This theory did hold true for boys. Those who scored high on the test were less likely to be obese than their peers with low or average scores.
But girls who scored either high or low were more likely to be obese by the time they reached kindergarten than those with average scores.
‘Although we tend to assume more self-regulation is always a positive, it may not be,’ said Dr Anderson.
‘We should not assume that interventions to increase self-regulation will necessarily lead to benefits for both genders – it may be different for boys and girls.’
She said that she believes the findings provide important information about the differences between the two sexes.
‘All we can do based on this research is speculate but it’s possible girls and boys are reacting differently to social expectations and that could play a role in childhood obesity,’ said Dr Anderson.
‘If you’re a boy and if the people around you are more OK with you getting easily frustrated and not paying attention, the social stress from your environment may be less than it is for a girl.’
She also adds that girls may be getting rewarded for ‘good’ behavior more often than boys.
Therefore, because the girls may be under more social pressure to exhibit better self-control, they put more pressure on themselves because they want to continue to satisfy the adults in their lives.
This pressure can extend to adulthood, where women put more pressure on themselves to be perceived as ‘perfect’.
‘These stresses might result in differences in energy balance and metabolism between girls and boys – especially in the group observed to have high self-regulation,’ said Dr Anderson.
For future research, the team hopes to look at other factors that could contribute to the link between obesity and self-control such as physiological differences, which affect food intake, appetite and levels of activity.
The study builds on previous research that shows the different implications obesity has for girls as opposed to boys.
A 2007 study showed that childhood obesity in girls could lead to the onset of early puberty.
And a study earlier this year found that girls who were obese in childhood could experience irregular periods as teens.